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United States Patent | 5,658,472 |
Bartha ,   et al. | August 19, 1997 |
A method is provided for producing deep substantially vertical structures in silicon substrates, wherein in a first step, the silicon substrate is anisotropically plasma etched to a first predetermined depth, thereby creating a first structure. Subsequently, the surface of the substrate is covered conformally with an etch-resistant coating, and the horizontal parts of said coating are selectively removed. Following this removal, the substrate is anisotropically plasma etched at low temperatures to a second predetermined depth with a mixture of SF.sub.6 /O.sub.2, whereby a second structure is created. Finally, the vertical parts of the coating are removed.
Inventors: | Bartha; Johann (Aidlingen, DE); Greschner; Johann (Pliezhausen, DE); Junginger; Robert (Boblingen, DE); Kraus; Georg (Wildberg, DE) |
Assignee: | International Business Machines Corporation (Armonk, NY) |
Appl. No.: | 477059 |
Filed: | June 7, 1995 |
Feb 24, 1995[DE] | 95102638.4 |
Current U.S. Class: | 216/2; 216/46; 216/79; 257/E21.232; 438/696; 438/700; 438/719 |
Intern'l Class: | H01L 021/82 |
Field of Search: | 437/228 156/662.1,651.1,653.1 216/46,79 |
4472240 | Sep., 1984 | Kameyama | 156/648. |
5194118 | Mar., 1993 | Shinohara | 156/643. |
5501893 | Mar., 1996 | Laermer et al. | 216/67. |
Foreign Patent Documents | |||
0366882A2 | Feb., 1989 | EP. | |
60-154622 | Aug., 1985 | JP. | |
02098925 | Apr., 1990 | JP. | |
WO94/14187 | Jun., 1994 | WO. |
Kenji Murakami, Yuji Wakabayashi, Kazuyuki Minami, Masayoshi Esashi, Crypgenic Dry Etching for High Aspect Ratio Microstructures, Jul. 2, 1993, pp. 65-70. Technical Disclosure Bulletin, Silicon Trench Formation Using Alternative Reactive Ion Etch And Oxidation, vol. 33, No. 2, p.351 (Jul. 1990). Christopher D'Emic, Kevin Chan, Joseph Blum, Deep Trench Plasam Etching of Single Crystal Silicon Using SF.sub.6 /O.sub.2, Jrnal of Vac. Science &Technology B 10(1992)May/Jun., No.3, New York, US, pp. 1105-1110. T. Kure, Y. Gotoh, H. Kawakami, S. Tachi, Highly Anisotropic Microwave Plasma Etching For High Packing Density Silicon Patterns, Feb. 6, 1992, pp. 48-49. "Reactive Ion Etching of Deep Isolation Trenches Using Sulfur Hexafluoride, Chlorine, Helium, and Oxygen"; Proc. SPIE-Int. Opt. Eng. (USA); vol. 1392; 1991; Krawiez et al.; abstract only. |